Battery control system and vehicle control system

Abstract

A battery control system connected to a battery, which controls charge/discharge at the battery, includes: a current detection unit that measures a current value by detecting a charge/discharge current flowing through the battery; a voltage detection unit that detects a voltage at the battery; a temperature detection unit that detects a temperature at the battery; an effective current value calculation unit that calculates, based upon the current value measured by the current detection unit, an effective current value in a predetermined time window; a time ratio calculation unit that determines a time ratio indicating a ratio of a length of time over which the effective current value has been in excess of a predetermined allowable value during a predetermined specified time period; and a charge/discharge restriction unit that restricts the charge/discharge current based upon the time ratio determined by the time ratio calculation unit.

The invention claimed is: 
     
       1. A battery control system connected to a battery, which controls charge/discharge at the battery, comprising:
 a current detection unit that measures a current value by detecting a charge/discharge current flowing through the battery; 
 a voltage detection unit that detects a voltage at the battery; 
 a temperature detection unit that detects a temperature at the battery; 
 an effective current value calculation unit that calculates, based upon the current value measured by the current detection unit, an effective current value in a predetermined time window; 
 a time ratio calculation unit that determines a time ratio indicating a ratio of a length of time over which the effective current value has been in excess of a predetermined allowable value during a predetermined specified time period; and 
 a charge/discharge restriction unit that restricts the charge/discharge current based upon the time ratio determined by the time ratio calculation unit. 
 
     
     
       2. The battery control system according to  claim 1 , wherein:
 the specified time period is at least 24 hours. 
 
     
     
       3. The battery control system according to  claim 1 , wherein:
 the charge/discharge restriction unit restricts the charge/discharge current when the time ratio is equal to or greater than 0.5. 
 
     
     
       4. The battery control system according to  claim 1 , wherein:
 the charge/discharge restriction unit clears restriction on the charge/discharge current once a length of elapsed time having elapsed since the restriction on the charge/discharge current came into effect or a total length of time over which the restriction on the charge/discharge current has been in effect exceeds a predetermined restriction clearance time. 
 
     
     
       5. The battery control system according to  claim 4 , wherein:
 the battery control system is connected to an in-vehicle communication network; and 
 the charge/discharge restriction unit obtains information pertaining to the length of elapsed time or the total length of time via the communication network. 
 
     
     
       6. A vehicle control system, comprising:
 a battery control system connected to a battery, which controls charge/discharge at the battery; and 
 a vehicle control unit connected with the battery control system, wherein: 
 the battery control system includes a current detection unit that measures a current value by detecting a charge/discharge current flowing through the battery, a voltage detection unit that detects a voltage at the battery, a temperature detection unit that detects a temperature at the battery and an effective current value calculation unit that calculates, based upon the current value measured by the current detection unit, an effective current value in a predetermined time window; and 
 the vehicle control unit determines a time ratio indicating a ratio of a length of time over which the effective current value has been in excess of a predetermined allowable value during a predetermined specified time period and issues an instruction for the battery control system so as to restrict the charge/discharge current based upon the time ratio having been determined.